The present invention relates to a vibration-absorbing damper used for an optical disk drive which is capable of absorbing vertical and horizontal vibrations.
Generally, an optical disk drive for recording or reading information on/from a disk, an optical recording medium, includes an optical pickup for emitting a laser beam to a predetermined position of the disk and for picking up the light reflected therefrom, a motor driving unit for rotating the disk and for moving the optical pickup, and a signal processing unit for processing the picked-up signal.
The optical disk drive constructed as described above rotates the disk by means of a driving motor and processes the data recorded on the disk as the optical pickup follows the tracks of the rotating disk. Thus, to correctly reproduce data, which is recorded on the disk with high density, the optical pickup is controlled by a tracking servo and a focus servo such that the beam of the optical pickup can be focused accurately onto the tracks of the disk.
However, when uncontrollable external impacts or vibrations are applied to a deck plate on which the optical pickup and the motor driving unit are installed, errors are generated during processing of the data of the optical disk drive.
Accordingly, a vibration-absorbing damper capable of absorbing vibrations and impacts and thus enabling stable data processing is required, which is to be installed between the deck plate, on which the optical pickup and the motor driving unit are installed, and a deck frame combined with the deck plate.
FIG. 1 shows an optical disk drive employing a conventional vibration-absorbing damper. As shown in the drawing, the optical disk drive is provided with a deck frame 5, which is part of a body. A deck plate 4, on which a turntable 7 having a disk (not shown) seated thereon and an optical pickup 6 for reading information from the disk are installed, is provided on the deck frame 5. Also, a plurality of dampers 3 for reducing vibrations transmitted from the deck frame 5 to the deck plate 4 are installed each being coupled by a screw 1 between the deck plate 4 and the deck frame 5.
Referring to FIG. 2, which illustrates the structure of the damper 3 in detail, the conventional damper 3 has an 8-shaped body in which cavities 3a having a circular planar section are formed, to absorb the external vibrations.
In the damper 3 having such a structure, when impacts or vibrations are transmitted from the outside to the deck frame 5, the damper 3 is elastically biased in a vertical direction within an elastically deformable range of the cavities 3a according to the external vibrations. Thus, the external vibrations can be absorbed by the cavities 3a as passing the damper 3. As a result, the external vibrations are hardly transmitted to the spindle motor for rotating the disk and the optical pickup 6. Thus, reproduction errors in the optical disk drive can be prevented.
However, since the above-described conventional damper 3 must be combined accurately using the screw 1, assembly of the optical disk drive becomes difficult. That is, if the screw 1 is not correctly coupled vertically or is overly screwed, the cavities 3a of the damper 3 cannot be elastically deformed sufficiently and thus the efficiency of absorbing vibrations is lowered. Also, if one of the screws is coupled loosely, the horizontal balance of the deck plate 4 cannot be maintained, which affects the deck plate 4 and other neighboring parts, such that performance of the optical disk drive is deteriorated. Furthermore, the conventional damper 3 sufficiently exhibits a vibration-absorbing characteristic in a vertical direction, but not in a horizonal direction due to its construction. Thus, it is to be installed only in the horizontal direction. In addition, hardness of material of each of the dampers 3 should be differentiated in accordance with the position of the center of gravity of the deck plate 4.